1. Field of the Invention
In general, the invention relates to digging tools, and more particularly, to post-hole digging tools with footrests.
2. Description of Related Art
A post-hole digger is a digging tool intended to dig deep, narrow holes for the placement of fence posts, sign posts, and other, similar structures. In a typical post-hole digger, the head of the tool includes two rounded digging blades that face one another and are connected to one another by a hinge. Each shovel head is connected to its own shaft. To use the device, the user drives the tool into the ground and then moves the handles to clamp down on some of the soil that the tool has sunk into before extracting the head, along with the soil, from the hole. The process is repeated until the hole is of sufficient size and depth.
With a typical post-hole digger, the user uses his or her arms to drive the tool into the ground. However, the typical tool does not allow the user to use his or her legs effectively in the process of driving the tool into the ground, and most people have more strength in their legs than in their arms. Thus, using a conventional post-hole digger can be tiring and inefficient.
Over the years, there have been isolated attempts to create post-hole diggers that allow a user to use his or her feet to drive the tool head into the ground, or to use other parts of the body for leverage. U.S. Pat. No. 5,669,648 to Luck is one example—the patent discloses post-hole diggers with a number of horizontal posts that are connected to the shafts with hinges, so that they can be swung up and out of the way if necessary. The horizontal posts can be used as foot rests for driving the tool head. However, the posts extend horizontally far beyond the tool itself, which may interfere with the soil when one tries to dig particularly deep holes. Moreover, the relatively long foot rests may increase the bending and tipping moments generated when pressure is applied, thus making the tool more difficult to use. Additionally, when the Luck tool is in use, dirt and soils may become lodged in the hinges of its foot rests, potentially causing the hinges to jam. If the foot rests open or the hinges jam open while the tool is in use, this could cause the foot rests to act like barbs on a hook, jamming the tool irretrievably in the hole. In fact, merely pulling the tool out of a hole may be enough to trigger the deployment of the foot rests.
The Luck patent recognizes an additional issue with post-hole diggers: when driving the tool into the ground, it is helpful if the two shafts can function as one rigid piece. Luck addresses this issue with a separate, detachable top plate assembly including a reinforcement bar that is attached between the shafts close to the top of the tool. While this may serve to rigidify the tool when it is driven, the top plate assembly and reinforcement bar prevent the tool from closing to remove soil when it is in place, and it may be inconvenient for a user to repeatedly attach and remove the top plate assembly while the tool is in use. Beyond that inconvenience, it is very easy for the user to lose a detachable piece of a tool like the top plate assembly, which would render its advantages moot.